FIELD OF THE INVENTION
This invention relates to a fitting for attachment to a pressurized valve or pressure containing component to be used to inject a sealant into the valve or component to eliminate or substantially reduce leakage there through. More particularly the invention relates to a fitting that provides a simpler more compact fitting that eliminates risks associated with using external valves or extensions, and at the same time provides additional and multiply redundant seals to further reduce or eliminate leakage from the fitting itself after installation.
The invention also more particularly relates to more recent applications under environmental regulations that require plugs on the open end of all valves. Problems arise because in the event the valve leaks there is no way to vent or purge the plug. The present invention has applications as a replacement for end plugs that allows multiply redundant seals and also allows the possibility of venting pressure from a leaking valve without allowing excess emissions into the environment.
Industrial complexes are characterized by miles of pressurized piping carrying products that may be hazardous should they be released to the environment. Low grade releases or leaks do occur, commonly associated with valuing used with the piping. A source of such leaks may be the deterioration of the packing along the valve stem. Sealant injected into the packing chamber of valves or into pipe clamps may eliminate or reduce such leaks. It is desirable and may be necessary at times to carry out such service while the valve or pipeline is still fully under pressure. These conditions dictate a need to carry out the service with a minimum exposure time for the technician.
Various approaches to the problems identified have been developed. The Preston U.S. Pat. No. RE. 23,526 was issued in 1952. It teaches an attachment body, a valve, and a containment body, which incorporates the stuffing box. Long extensions of these components are required to install the final plug, and no multiple seals are provided. The Reddy U.S. Pat. No. 2,763.282 issued in 1956. It teaches similarly to the Preston reference. U.S. Pat. No. 5,052,427, to Butler, et al., issued in 1991 adds the variation of attaching the fitting to the valve by friction welding rather than drilling and tapping threads. This reference still requires a series of multiple components creating a risk of knock off from the cantilever effect of a drill or injection gun, connected to a packing gland, in turn connected to a valve which would finally be connected to the attachment fitting. The combination of components and their configuration does not teach or allow for the multiple redundant seals of the present invention. Additionally, unless utilized in its separate components, the ability to use friction welding, which requires high rotational speeds, is greatly impaired by the unbalanced protrusions of the pin forming the fitting valve.